Axis Physiology Flashcards
hypothalamic- pituitary axis
hypothalamus secretes hormones that act on pituitary > pituitary secretes other hormones that act on peripheral tissues
name some hypothalamic hormones that act on pituitary and some pituitary hormones that are secreted
CRH > ACTH > cortisol
TRH > TSH > T3 & T4
GnRH > LH/FSH > oes etc
GHRH > GH > IGF-1
name some other axis
hypo-thyroid axis adrenal axis GH axis parathyroid axis hypo-gonadal axis
cortisol is released in a _____ fashion and also if under _____
diurnal (peak at 9am) and stress
when is PTH secreted from parathyroid glands
low serum Ca, Mg, or high sulphate
what does PTH do?
inc osteoclast activity, inc bone resorption from DCT and converts VitD > Calcitriol
action of aldosterone
inc Na reabsorption in DCT of kidneys
inc K secretion in DCT
inc H+ secretion in collecting ducts
GnRH is released by hypothalamus in a ______ manner
pulsatile
T/F: high frequency pulses release LH
T: high frequency GnRH pulses secrete LH, low frequency pulses secrete FSH
which out of oestrogen and progesterone inc GnRH pulsatility and which dec pulsatility
oestrogen: inc
progesterone: dec
how do the gonadotrophs influence pulsatility of GnRH
by influencing kisspeptin neurones
T/F: aldosterone is secreted by hypothalamic regulation on pituitary gland
F: Aldosterone secreted in response to RAAS
cortisol and androgen secreted with hypothalamic influence over pituitary
